Whenever you use the Internet to send and receive email or read a web page or even watch Netflix, your computer or smartphone sends data packets to computers at the other end of your connection. Each data packet includes all the information to make sure it arrives at the server you are connecting to and that the server can then send more data back to you. In addition, anyone that with access to the data connection can tell what types of data you are transferring, etc.
If you are not using Encryption or a VPN, someone at your office with a packet sniffer can tell not only what type of traffic you are sending on the internet, but in the case of things like email, what the contents of your emails are. Besides the nosy neighbor in the next cubicle, the data can also be viewed by your ISP (cell phone company for smartphones), or by the operator or someone with a packet sniffer at your local Internet cafe.
To protect sensitive data, most corporations now require their employees to connect to their office using a VPN. With a properly installed and configured VPN all data between your PC and the server are encrypted through a private connection that is supposed to be impossible for anyone in the middle to decode. This is accomplished using private and public keys for establishing the connection, so certain parts of the initial conversation are known at each end, and never transmitted leaving out a crucial piece needed to decode the data.
I have worked with VPNs for years, and have even written a couple in my days for clients that needed secure connections over an old Frame Relay connection. Modern VPNs make my little package pale by comparison, but the goals are still the same, protect your information from people you don’t want to have access to it. New VPNs are showing up every day, and I have decided to start providing reviews on some of them as I test them for myself and/or my clients.